1. Field of the Invention
The invention relates to amphiphilic compounds with at least two hydrophilic and at least two hydrophobic groups based on amides.
2. Description of the Background
A wide variety of anionic, cationic, nonionic and zwitterionic compounds are known as amphiphilic substances. By far the most of these substances consist of a hydrophilic head group and at least one hydrophobic part.
With the amphiphilic substances there is a need, for ecological reasons, for example concerning the reduction in the cost of packaging and transport, to achieve an increasingly greater effect per mass of substance employed. Since optimization by mixing amphiphilic substances produces only very limited advances, novel amphiphilic substances with greater efficiency are required. It is therefore necessary in particular to find substances with lower critical micelle concentrations and/or lower surface and interfacial tensions in order to be able to reduce markedly the amounts of active substance employed.
Initial approaches to a solution in this direction by doubling one part of the structure (hydrophilic head group, hydrophobic group) have already been disclosed. Thus, cationic surface-active compounds can be obtained by adding long-chain alkyl halides onto permethylated alkylenediamines [R. Zana, M. Benrraou, R. Rueff, Langmuir, 7 (1991) 1072: R. Zana, Y. Talmon, Nature, 362 (1993) 228; E. Alami, G. Beinert, P. Marie, R. Zana, Langmuir, 9 (1993) 1465].
Nonionic amides having a gemini structure are described in EP-A-O 258 923. They are employed in specific plasticizer and surfactant compositions and employed together with water-soluble quaternary ammonium compounds and a clay of a certain minimum ion-exchanger capacity.
Anionic surface-active compounds with at least two hydrophilic and at least two hydrophobic groups have to date been prepared only on the basis of diglycidyl ethers (U.S. Pat. No. 5,160,450, JP 01 304 033, JP 4 124 165). However, diglycidyl ethers are regarded as toxicologically objectionable and are rather costly. Furthermore, epichlorohydrin is used for their preparation, which leads to large amounts of residues so that these compounds are no longer in accord with the times from the ecotoxicological and economic viewpoints.
The object therefore was to find amphiphilic compounds which have at least two hydrophilic and at least two hydrophobic groups, the amphiphilic compounds having a very high efficiency relative to the amount used, and which furthermore can be prepared from raw materials which are easily available industrially and without large amounts of unwanted by-products being formed.
The object is achieved according to the invention by amphiphilic di- or oligoamides whose basic skeletons can be prepared from di- or oligoamines and fatty acids or fatty acid methyl esters. The corresponding di- or oligoamides can be alkoxylated. These nonionic amphiphilic compounds can be converted into anionic amphiphilic compounds by, for example, reacting the abovementioned compounds with SO3/inert gas (or oleum or chlorosulfonic acid), with polyphosphoric acid, with a haloacetic acid, with a sultone or with a taurine and, in each case, subsequently neutralizing.
The amphiphilic compounds according to the invention are therefore compounds of the general formula I 
where R1, R2, R3, X, Y and Z in formula I have the meanings described below:
R1 and R3 are, independently of one another, an unbranched or branched, saturated or unsaturated hydrocarbon radical with 1 to 22, preferably 7 to 17, carbon atoms.
Specific substituents R1 and R3 which may be mentioned are the radicals methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, n-uneicosyl, n-docosyl and their branched-chain isomers, and the corresponding singly, doubly or triply unsaturated radicals.
R2 is a spacer consisting of an unbranched or branched chain with 2 to 100 carbon atoms, which in each case contains 0 to 20 oxygen and nitrogen atoms and 0 to 4 sulfur atoms and 0 to 3 phosphorus atoms, and which has 0 to 20 functional side groups such as, for example, hydroxyl, carbonyl, carboxyl, amino and/or acylamino groups.
The spacer R2 is, in particular,
as basic skeleton, unbranched or branched alkylene chains
xe2x80x94CaH2axe2x80x94xe2x80x83xe2x80x83(II)
with a=2 to 18, preferably a=3 to 6;
as basic skeleton, unbranched or branched alkenylene chains
xe2x80x83xe2x80x94CbH2bxe2x80x94CHxe2x95x90CHxe2x80x94CcH2cxe2x80x94xe2x80x83xe2x80x83(III)
with b+c=2 to 16, where b and c are each greater than zero;
as basic skeleton, unbranched or branched alkynylene chains
xe2x80x94CdH2dxe2x80x94Cxe2x89xa1Cxe2x80x94CeH2exe2x80x94xe2x80x83xe2x80x83(IV)
with d+e=2 to 16, where d and e are each greater than zero, and where in the basic skeletons according to formulae II to IV the spacer contains at any desired point in the chain additionally 0 to 4 carbonyl, amino or acylamino groups;
alicycles according to the formula V
xe2x80x94CfH2f-cyclo C6H10xe2x80x94CgH2gxe2x80x94xe2x80x83xe2x80x83(V)
with f and g=each 1 to 6
or according to formula VI
-3(4),8(9)-di(methylene)-tricyclo [5.2.1.02.6]decane-xe2x80x83xe2x80x83(VI);
unsubstituted or substituted aromatics according to the formula VII
xe2x80x94ChH2hxe2x80x94C6R4xe2x80x94(CiH2ixe2x80x94C6R4)j1xe2x80x94Cj2H2j2xe2x80x94xe2x80x83xe2x80x83(VII)
or according to the formula VIII
xe2x80x94ChH2hxe2x80x94C10R6xe2x80x94CjH2jxe2x80x94xe2x80x83xe2x80x83(VIII)
with h, j, j1 and j2=each 0 to 8 and i=1 to 8 and with R=independently of one another in each case H or C1- to C4-alkyl;
a chain with functional side groups, in particular an amino, acylamino, carbonyl or carboxyl functionality.
Furthermore, the spacer R2 in each case contains 0 to 20, preferably 1 to 12, oxygen and/or nitrogen atoms, 0 to 4 sulfur atoms and 0 to 3 phosphorus atoms, with at least one of the heteroatoms occurring at least once.
R2 thus furthermore has in particular the meaning
of a compound according to the formula IX
xe2x80x94CkH2kxe2x80x94CxRyxe2x80x94Zxe2x80x94CxRyxe2x80x94ClH2lxe2x80x94xe2x80x83xe2x80x83(IX)
with k and l=each 0 to 8, x=6 and y=4 or x=10 and y=6 or x=14 and y=8, and Z=O, NH, NR1, Nxe2x80x94C(O)R1, SO2, where R1 is a hydrocarbon radical with 1 to 22 carbon atoms and R is, independently of one another, in each case H or C1-C4-alkyl;
of a compound according to the formula X
xe2x80x94CmH2mxe2x80x94(OCnH2n)pxe2x80x94CqH2qxe2x80x94xe2x80x83xe2x80x83(X)
with m=1 to 4, n=2 to 4, p=1 to 20, preferably p=1 to 4 and q=1 to 4, where mixed alkoxide units may also occur and then the sequence of the alkoxide units is arbitary;
of a compound according to the formula XI
xe2x80x94CrH2r(RNCsH2s)txe2x80x94CuH2uxe2x80x94xe2x80x83xe2x80x83(XI)
or according to the formula XII
xe2x80x94[CrH2r[RNxe2x80x94C(O)xe2x80x94NR]txe2x80x94CuH2u]wxe2x80x94xe2x80x83xe2x80x83(XII)
or according to the formula XIII
xe2x80x94[CrH2r[RNC(O)CvH2vC(O)NR]txe2x80x94CuH2u]wxe2x80x94xe2x80x83xe2x80x83(XIII)
or according to the formula XIV
xe2x80x94[CrH2r[RNxe2x80x94C(O)xe2x80x94CHxe2x95x90CHxe2x80x94C(O)xe2x80x94NR]txe2x80x94CuH2u]wxe2x80x94xe2x80x83xe2x80x83(XIV)
or according to the formula XV
xe2x80x94[CrH2r[RNC(O)CxRyC(O)NR]tCuH2u]wxe2x80x94xe2x80x83xe2x80x83(XV)
with r=2 to 4, s=2 to 4, t=1 to 20, preferably t=1 to 4, u=2 to 4, v=0 to 12, w=1 to 6, x=6 and y=4 or x=10 and y=6 or x=14 and y=8 with R=independently of one another in each case H or C1- to C4-alkyl.
X or Y is a substituent of the formula XVI
xe2x80x94(C2H4O)xcex1(C3H6O)xcex2Hxe2x80x83xe2x80x83(XVI)
with xcex1=0 to 50, preferably xcex1=10 to 30, xcex2=0 to 60, preferably xcex2=20 to 40, and xcex1+xcex2=1 to 100, preferably xcex1+xcex2=10 to 50, where R2 is not C2H4 when xcex2=0,
and X or Y is a substituent of the formula XVII or X and Y are, independently of one another, substituents of the formula XVII
xe2x80x94(C2H4O)65 (C3H6O)xcex4xe2x80x94FRxe2x80x83xe2x80x83(XVII)
with in each case
xcex3=to 20, preferably xcex3=0 to 8,
xcex4=0 to 20, preferably xcex4=0 to 12, and xcex3+xcex4=1 to 40, preferably xcex3+xcex4=5 to 20,
where the alkoxide units are incorporated randomly or blockwise and the sequence is arbitrary and where FR is a functional radical xe2x80x94CH2xe2x80x94COOM, xe2x80x94SO3M, xe2x80x94P(O(OM)2, xe2x80x94Oxe2x80x94C(O)xe2x80x94C2H3(SO3M)xe2x80x94CO2Mxe2x80x2 or xe2x80x94C2H4xe2x80x94SO3M with M, Mxe2x80x2=alkali metal, ammonium, alkanolammonium or xc2xd alkaline earth metal.
The degree of oligomerization Z is 1 to 10, preferably Z=1 to 4, particularly preferably Z=1.
The degree of alkoxylation is in each case an average and can assume any desired, including non-integral, value within the stated limits.
The amphiphilic compounds according to the invention are usually distinguished by extremely low critical micelle concentrations (CMC) and very low surface and interfacial tensions (for example in the presence of paraffin), which must be ascribed to their special structurexe2x80x94at least two hydrophilic groups and at least two hydrophobic groups. Furthermore, most of them display a rather high hydrophilic suspension capacity which is about halfway between that of conventional surfactants and that of pentasodium tripolyphosphate. Some of these compounds are extremely rapid wetting agents.
The amphiphilic compounds according to this invention are particularly suitable as emulsifiers, demulsifiers, detergents, dispersants and hydrotropes in industry and domestically, for example in the areas of metal processing, ore production, surface treatment, washing and cleaning, cosmetics, medicine and foodstuff processing and preparation.
In these cases they can be combined with all customary anionic, nonionic, cationic and ampholytic surface-active substances. Examples of nonionic surface-active substances which can be used for a combination and which may be mentioned are: fatty acid glycerides, fatty acid polyglycerides, fatty acid esters, ethoxylates of higher alcohols, polyoxyethylene fatty acid glycerides, polyoxyethylene/propylene glycol fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene castor oil or hardened castor oil derivatives, polyoxyethylene lanolin derivatives, polyoxyethylene fatty acid amides, polyoxyethylene alkylamines, alkanolamines, alkylamine oxides, derivatives of protein hydrolysates, hydroxy-mixed ethers, alkyl polyglycosides and alkylglucamides.
Examples of anionic surface-active substances which can be used for combinations and which may be mentioned are: soaps, ether carboxylic acids and salts thereof, alkylsulfonates, xcex1-olefinsulfonates, sulfonates of higher fatty acid esters, higher alcohol sulfates, alcohol ether sulfates, hydroxy-mixed ether sulfates, salts of phosphate esters, taurides, isethionates, linear alkylbenzenesulfonates, cumenesulfonate, alkylarylsulfonates, sulfates of polyoxyethylene fatty acid amides and salts of acylamino acids.
Examples of customary cationic surface-active substances which can be used for combinations and which may be mentioned are: alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, alkylpyridinium salts, alkylisoquinolinium salts, benzethonium chlorides and cationic acylamino acid derivatives.
Examples of ampholytic surface-active substances which can be used for combinations and which may be mentioned are: amino acids, betaines, sulfobetaines, imidazoline derivatives, soybean oil lipids and lecithin.
Furthermore, the amphiphilic compounds according to the invention can also be combined together on their own. It is likewise possible to add conventional additives to the amphiphilic compounds according to the invention. Such additives are specifically selected for a formulation and normally comprise inorganic salts such as sodium chloride and sulfate, and builders, hydrotropes, UV absorbers, softening agents, chelating agents, viscosity modifiers and fragrances.
The abovementioned compounds can be prepared by known methods: the di- or oligoamines are reacted with, in each case, one equivalent of fatty acid or fatty acid methyl ester per free NH functionality at elevated temperatures (80 to 180xc2x0 C.), optionally in the presence of a catalyst, removing the water which is produced or the methanol under vacuum. Subsequently, alkoxylation is carried out at temperatures from 130 to 190xc2x0 C. in the presence of a basic catalyst. The products are liquids or soften at low temperatures and can subsequently be reacted with SO3/inert gas (oleum or chlorosulfonic acid) or polyphosphoric acid or with a haloacetic acid, a sultone or with isethionic acid and neutralized with aqueous alkali metal or alkaline earth metal hydroxides or aqueous ammonia or alkanolamines. If required, the products are bleached in aqueous solution with hydrogen peroxide (0.1 to 2.0% based on solids).